Require SystemCommand only where needed

[dduugg]

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Continuation of #16538

This removes SystemCommand::Mixin from the top-level namespace, and instead includes it only in the needed namespaces.

[dduugg]

Homebrew/homebrew-test-bot#1004 is an attempt to fix the failing check

[apainintheneck]

It looks like this is also used in Casks which seems to be covered here and in two cask repo commands as well.

• changed_files.rb
• check.rb
  • It's used in a few places throughout this file but I just highlighted the first one.

@bevanjkay @reitermarkus How hard would it be to replace these uses of system_command with other methods?

[dduugg]

It looks like this is also used in Casks which seems to be covered here and in two cask repo commands as well.

• changed_files.rb

• check.rb

  • It's used in a few places throughout this file but I just highlighted the first one.

@bevanjkay @reitermarkus How hard would it be to replace these uses of system_command with other methods?

It looks like we can require brew paths in this repo, e.g. https://github.com/Homebrew/homebrew-cask/blob/fb9cc3d4e7083471a99ae4808684d09458c9bcba/cmd/lib/generate-matrix.rb#L4

If so, we should be able to require "system_command" and include/extend SystemCommand::Mixin where appropriate. Does that seem possible?

[Bo98]

@bevanjkay @reitermarkus How hard would it be to replace these uses of system_command with other methods?

They should probably be replaced with public API like Utils.safe_popen_read that's less likely to be volatile to changes. The SystemCommand::Mixin refactor here should largely be an internal thing (test-bot is OK).

[dduugg]

It looks like this is also used in Casks which seems to be covered here and in two cask repo commands as well.

• changed_files.rb

• check.rb

  • It's used in a few places throughout this file but I just highlighted the first one.

@bevanjkay @reitermarkus How hard would it be to replace these uses of system_command with other methods?

It looks like we can require brew paths in this repo, e.g. https://github.com/Homebrew/homebrew-cask/blob/fb9cc3d4e7083471a99ae4808684d09458c9bcba/cmd/lib/generate-matrix.rb#L4

If so, we should be able to require "system_command" and include/extend SystemCommand::Mixin where appropriate. Does that seem possible?

I went ahead and opened a PR to do just this: Homebrew/homebrew-cask#165732